How can I share and edit multitrack files with someone in another state?

I am working on a podcast with a colleague in another state.  We both have purchased Audtion.

We have collected clips in a Google drive and are able to edit those fine.

When I create a mulittrack session, however, she can't work on it at her end.  When she opens the sesx file, the clips I've added show up, but they aren't linked to anything and there's no sound.  

Is there a system we can use to collaboratively edit multitrack sessions? 

For ex, can we use Creative Cloud libraries?  Or is there a way to re-link the files to the multitrack session when we open it from a new computer?